This Tasty Diet Can Prevent Heart Attacks And Strokes, Study Says

A large study conducted with funding from the Spanish government appears to have settled an old debate: What should people eat to avoid having a heart attack or stroke? It turns out it may not be how much fat you eat but what kind.

Patients who ate a “Mediterranean” diet rich in nuts or extra virgin olive oil as well as vegetables and wine had 30% fewer heart attacks, strokes, or deaths from cardiovascular disease than those that ate a diet that simply lowered their intake of dietary fat. The result, cardiologists say, is likely to change what doctors advise patients who are at risk of cardiovascular disease to eat. The study is being published in the New England Journal of Medicine and presented at the International Congress on Vegetarian Nutrition in Loma Linda, Calif.

Steven Nissen, chairman of the department of medicine at the Cleveland Clinic, called it “an outstanding study with broad societal implications,” noting that the benefit was as big as might be seen with the powerful cholesterol-lowering statin drugs that have become a mainstay of cardiology. He said the result shows “how science can dispel a widely held but fundamentally wrong public opinion”: in this case that an ultra-low-fat diet can make people heart attack proof. Harlan Krumholz, a cardiologist at Yale University and a Forbes contributor, called the result “game-changing.”

“The big issue here is not to cut the total amount of fat in the diet,” says Miguel Martinez-Gonzalez, Professor and Chair of the Department of Preventative Medicine at the University of Navarra and senior author of the study. “If you cut the amount of fat in the diet people will not comply. This is the advantage of the Mediterranean diet. It is high in fat, but it is healthy fat.”

The study carries much more scientific weight than most other studies of diet, which simply examine what it is that healthy people eat. A person who avoids red meat, for instance, might be doing all sorts of other things to remain healthy. What Martinez-Gonzalez and his colleagues did was to test the Mediterranean diet as if it were a drug, in a gold-standard randomized controlled clinical trial.

They recruited 7,447 men and women in Spain between the ages of 55 and 80 who had high blood pressure, high cholesterol, or other risk factors for heart disease but had not had heart problems yet. The researchers randomly assigned these patients to three groups, who were put on three different diets:

A Mediterranean diet high in vegetables, beans and other legumes, fruits, and fish, with at least 4 tablespoons of extra virgin olive oil a day. They were provided with a liter of the oil weekly for the use of their families. If they drank alcohol, they were told to consume at least seven glasses of wine a week. Cookies and other bakery treats, spreads like butter, and processed and red meats were discouraged.A nearly identical Mediterranean diet that instead of extra-virgin olive oil included walnuts, almonds, and hazelnuts. People were advised to consume 30 grams of nuts a day, which they were given for free.Patients in the control group were told to avoid fat, including removing any visible fat from food (cooling and scraping it off the top of soup, for instance). They were even to avoid fatty fish. These people received small gifts as part of the study.